[JaZZ]

But the 1-M-Scaler will be presented at Canjam London, no?

 

[DaveRedRef-III]

Maybe the M Scaler is enough Rob, though I expect further improvements can be found in time. Looking forward to learning about your Davina findings in time. I may even buy one and start recording again.

 

[Rob Watts]

But the 1-M-Scaler will be presented at Canjam London, no?

You will find out pretty soon!

Maybe the M Scaler is enough Rob, though I expect further improvements can be found in time. Looking forward to learning about your Davina findings in time. I may even buy one and start recording again.

The 705/768 to 44.1/48 decimation filters were tested last week; they work perfectly, absolutely no aliasing (to 24 bit rounding error). Next step is the 104 MHz to 705/768 decimation filters, and that I hope design will start next week. Its a non trivial design, as again zero aliasing is the goal, from 104 MHz down to 768k. Once that is done, then hardware testing of Davina will start.

I think a huge number of questions will get answered with this project - hopefully some unexpected things will get discovered, and who knows where that will lead...

Rob

 

[Jawed]

Is the intention that the ADC samples 5-bit at ~104MHz and decimates to 16FS at 24-bit?

If you need a super high resolution speaker system to judge the quality of Davina recordings, will it be possible for these listening tests to be meaningful if you don't have a power pulse array amplifier that equals, or betters, DAVE's pulse array?


Now playing: The Cure - Play for Today

 

[Rob Watts]

Chicken and egg comes to mind. We are already using, what I see, as seriously flawed recordings - ADC's that have huge aliasing issues (creating transient timing errors), large amounts of measurable noise floor modulation, and measurable small signal amplitude nonlinearity, against my DACs that have non of these things, at least from a measurable POV.

Given the above, I am expecting to hear a massive change via a Mojo and inexpensive headphones - let alone Dave. Of course, Davina project should allow improvements of DACs and amps in the future for a variety of reasons; complete control of transducer end to end, plus overall performance being so much better, thus making subtle differences more pronounced. I am already seeing this now; things that were small in the past are a lot easier to hear via the M scaler. But I also have Dave plus headphones as a benchmark; plus TT2 on my 803 D3. And I suspect other developments would have happened by the time a quantity of Davina project recordings are available.

As too your first point, its 6 bits 104MHz (plus perhaps an extra OL bit) to 24 bit at 16FS.

 

[musickid]

I wonder could Xilink not produce a custom designed fpga that would meet your requirements? The cost could be trickled down to us?

 

[x RELIC x]

I wonder could Xilink not produce a custom designed fpga that would meet your requirements? The cost could be trickled down to us?

Custom = $$$$$$$$$$$$$$

 

[musickid]

Comprende

 

[Rob Watts]

A state of the art mask set (7nm is being taped out now) would cost $150 million; Xilinx revenues is only $2,540 million. So getting economic low cost silicon at lower process nodes will be a long wait.

 

[musickid]

Imagine a number of dac's that had access to an unlimited amount of superconductor processing "power" available 24/7 in the cloud in much the same way that torrent files work each user sharing and contributing all regulated by AI. Apologies off on a tangent here.

 

[darkless]

@Rob Watts Would an inline BNC lowpass filter (linked below) be a viable alternative to adding ferrites to the coax cables connecting the Blu2 and DAVE?

Datasheet for BLP-7-75+

 

[Triode User]

@Rob Watts Would an inline BNC lowpass filter (linked below) be a viable alternative to adding ferrites to the coax cables connecting the Blu2 and DAVE?

Datasheet for BLP-7-75+

Rob is a better source of info than me but my best guess is that they would not work because the RF we are talking about from the Blu2 is in the ground plane and those filters you mention only apply to the centre signal conductor.

 

[Rob Watts]

Yes that's correct - it's the ground currents we need to reduce, and this filter has no effect on these currents, as gnd is not filtered. Only ferrites can reduce blu2/Dave RF common mode ground currents.

 

[HeeBroG]

Yes that's correct - it's the ground currents we need to reduce, and this filter has no effect on these currents, as gnd is not filtered. Only ferrites can reduce blu2/Dave RF common mode ground currents.

Hi Rob,

Does a metal braid around the BNC cable have a similar effect on RF as the Ferrites?
Some users on ComputerAudiophile report good RF filtering results on DC/USB cables and I am guessing the same would apply to a BNC cable delivering digital data.
There is a so called "JSSG 360" cable modification; after John Swenson, which has a dual layer metal braid with a dielectric sandwiched in between but connected at both ends to create an electrical loop. The shield is not connected to the connectors at either end but "floating".

 

[AndrewOld]

Hi Rob,
Does a metal braid around the BNC cable have a similar effect on RF as the Ferrites?

Only ferrites can reduce blu2/Dave RF common mode ground currents.